A lot of understeer
07-29-2007, 09:50 PM
#27
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The way the 8 is balanced, it should be very neutral in a corner (assume DSC is off). A 4-wheel power slide is a sign of a well-balanced car. Another nice thing about that is with some minor tweaking, you can dial in some oversteer if you want, like if you want to pitch the rear end around a little more for cornering.
07-30-2007, 03:16 AM
#28
ok,
simple what tires were on the car? and what was the pressure of the said tires???
likely that is the problem...
beers
simple what tires were on the car? and what was the pressure of the said tires???
likely that is the problem...
beers
Don't take my comment the wrong way (when I said about not pushing the car). I test drove it for less than 24 hours and the "amount" of understeer was significant. Then some of you said that "never" felt it or that the car was very stable/nautral. That made me believe that either some of you did not push the car like I did or that there was something wrong with the one I drove. That's all.
The botton line is that I was trying to share what I found and hoping to get some feedback on may be how to fix the understeer, like getting utra-performance tires, etc.
The botton line is that I was trying to share what I found and hoping to get some feedback on may be how to fix the understeer, like getting utra-performance tires, etc.
07-30-2007, 06:29 AM
#29
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i was bumping an old thread instead of starting a new one, i don't know if the OP is even active anymore... so i guess it's really my question
just to clarify i've noticed understeer, not in cornering, but at the point where i USED to oversteer and break the back end loose, i've been understeering and started to slide, then plow. i suspect it is my tires as i've noticed big pressure changes recently, which is why i picked this post to bump...
at the time when i last plowed the tire pressure was 40psi (pumped to 32, 40 with heat)
when people say "it's probably your tires" i don't exactly know what that means. i've suspected the same thing, but is it most likely my tread? pressures being too high? to low?
just to clarify i've noticed understeer, not in cornering, but at the point where i USED to oversteer and break the back end loose, i've been understeering and started to slide, then plow. i suspect it is my tires as i've noticed big pressure changes recently, which is why i picked this post to bump...
at the time when i last plowed the tire pressure was 40psi (pumped to 32, 40 with heat)
when people say "it's probably your tires" i don't exactly know what that means. i've suspected the same thing, but is it most likely my tread? pressures being too high? to low?
07-30-2007, 06:59 AM
#31
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https://www.rx8club.com/showpost.php...50&postcount=3
i might've found my answer here, i've had about 16 runs (runs, not events) in auto cross, and i may or may not have spun, done donuts, etc while trying to learn how to break the back end loose.
however would hard tires make me understeer into a plow? i would think since the power is in the rwd, the backs would spin first making it oversteer instead.
i might've found my answer here, i've had about 16 runs (runs, not events) in auto cross, and i may or may not have spun, done donuts, etc while trying to learn how to break the back end loose.
however would hard tires make me understeer into a plow? i would think since the power is in the rwd, the backs would spin first making it oversteer instead.
07-30-2007, 07:01 AM
#32
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08-13-2009, 09:06 PM
#34
MMMMM............BACON!
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Sorry to bump this thread back to life but in the last week my car has started to understeer drastically. Corners on the back roads to my house that I used to take at 45 or so nice and easily now induce understeer at about 30 MPH. This literally started happening almost all of the sudden....one day she drives great next she handles like she is now. I was just curious what could cause an almost instant change in driving characteristics of the car. ?!?!
08-14-2009, 01:40 AM
#35
Sorry to bump this thread back to life but in the last week my car has started to understeer drastically. Corners on the back roads to my house that I used to take at 45 or so nice and easily now induce understeer at about 30 MPH. This literally started happening almost all of the sudden....one day she drives great next she handles like she is now. I was just curious what could cause an almost instant change in driving characteristics of the car. ?!?!
beers
08-14-2009, 02:33 AM
#36
Do Kumho Ecsta SPT's tend to understeer alot? I just remember taking some corners slow at first then almost understeering, the car wanted to keep going straight which is why i thought i took it too hot but i wasn't going that fast... I was thinking it probably has to be the tire and not the car because i can get the back end out pretty easily...
O and Swoope wasnt it you that pointed me to the SPT's in the first place right? lol
O and Swoope wasnt it you that pointed me to the SPT's in the first place right? lol
Last edited by WTBRotary!; 08-14-2009 at 02:36 AM.
08-14-2009, 03:22 AM
#37
Do Kumho Ecsta SPT's tend to understeer alot? I just remember taking some corners slow at first then almost understeering, the car wanted to keep going straight which is why i thought i took it too hot but i wasn't going that fast... I was thinking it probably has to be the tire and not the car because i can get the back end out pretty easily...
O and Swoope wasnt it you that pointed me to the SPT's in the first place right? lol
O and Swoope wasnt it you that pointed me to the SPT's in the first place right? lol
no the spt does not understeer. tire pressures and suspensions would be the likely culprit..
i have done track days on the spt. and rode along with an instructor running the spt..
it is not a name that tire issue. it is a balance issue..
what tire pressures are you running? are we just talking about the street? suspension?
and as to the spt. i have a older set that are going back on the car.. the star specs are coming off!
beers
08-14-2009, 09:11 AM
#41
I thought the tires were a problem when I went to the autox, I had understeer pretty bad, but after thinking about it, it was 10% tires, and 90% poor driving. I had the stock tires though.
08-14-2009, 10:29 AM
#42
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yeah nearly 50/50 weigh distribution is when no centrifugal force is involved.
The moment you press hard on the brake pedal, my estimate is probably 60/40 if not worse???
I suck at physics, I'd like to know the actual weigh distribution under hard braking though. Also, hard acceleration as well.
The moment you press hard on the brake pedal, my estimate is probably 60/40 if not worse???
I suck at physics, I'd like to know the actual weigh distribution under hard braking though. Also, hard acceleration as well.
08-14-2009, 12:23 PM
#44
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The SPTs aren't the stickiest tire compared to competitor's but they aren't going to act like some all-season cheapies. What tire pressure do you have? Bump them a couple pounds higher than recommended tire pressure. It helps the tires stiffen the sidewalls. The SPTs do tend to start squealing when you get them to where they start to go.
08-14-2009, 02:06 PM
#45
Yes they do squeal but they are WEARING very fast, my alignment isnt too agressive but my normal tire pressure is around ~32 normally... Idk why they are wearing fast I can try to find my alignment and post the specs later but ive gone around a highway off-ramp thats like a huge 360 around 15-17 times in the last month with the tires squealing a little and ive noticed they have worn ALOT... these tires only have around ~8k miles on them... I mean they are supposed to last to roughly 25K with normal driving no? Im not on stock suspension either im lowered on Tein S. Techs as well as Koni Yellows...
08-14-2009, 02:16 PM
#46
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Yes they do squeal but they are WEARING very fast, my alignment isnt too agressive but my normal tire pressure is around ~32 normally... Idk why they are wearing fast I can try to find my alignment and post the specs later but ive gone around a highway off-ramp thats like a huge 360 around 15-17 times in the last month with the tires squealing a little and ive noticed they have worn ALOT... these tires only have around ~8k miles on them... I mean they are supposed to last to roughly 25K with normal driving no? Im not on stock suspension either im lowered on Tein S. Techs as well as Koni Yellows...
Making the tires squeak & squeal is hardly "normal driving" lol
08-14-2009, 02:18 PM
#47
Which makes me think they would last to roughly 18k... but these should be kinda hard compound no? I mean i know every tire manufacturer sets their own tire rating but these have a 320... which is around 27k... I drive alot but these havent even had like 6 months on them yet... sigh any ideas?
08-14-2009, 03:31 PM
#50
The Michigan "WANKEL"
I have experienced occasional understeer with my new RX-8. A lot of it depends on how you're driving through the turn. I've even gotten my Mazda3 (with Koni Sport dampers, Racing Beat springs, and Progress rear anti-roll bar) to swing it's butt out a bit around a 180 degree "Michigan left" I take frequently with the proper combination of steering and throttle.
My RX-8 has been a learning experience. Up until 4 months ago when I purchased my RX-8, all of my real driving (as opposed to simulators with a full-on racing cockpit I have at home), including the Mid-Ohio School, has been in front-heavy FWD cars. But my RX-8 can experience some understeer on the stock Dunlops under the right conditions (which I'm still trying to figure out). However, I have definitely figured out how to bring the back end around in severe (intentional) oversteer for kicks and giggles.
My RX-8 has been a learning experience. Up until 4 months ago when I purchased my RX-8, all of my real driving (as opposed to simulators with a full-on racing cockpit I have at home), including the Mid-Ohio School, has been in front-heavy FWD cars. But my RX-8 can experience some understeer on the stock Dunlops under the right conditions (which I'm still trying to figure out). However, I have definitely figured out how to bring the back end around in severe (intentional) oversteer for kicks and giggles.